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The Welsh Government’s traffic information service for motorways and trunk roads in Wales

M4 Port Talbot Bypass Safety Measures FAQS

defect in column of M4 Port Talbot Bypass

Netting and fencing works will take place under the M4 on four structures forming the M4 Port Talbot Bypass, Dyffryn, Tan y Groes, Afan and Llewellyn Street. to ensure public safely during investigation works.

The South Wales Trunk Road Agent (SWTRA) has identified localised areas of delaminating concrete at each structure. To manage the risk ground level inspections will be taking place every 2 weeks as well as close inspections at high risk areas on a quarterly basis. In advance of repair works and to further lower the risk of falling concrete additional safety measures are now required. 

Please click below for the proposed netting and fencing arrangements on the four structures.

The areas where concrete is delaminating are to be fenced and or netted to prevent access from the public.  SWTRA on instruction from the Welsh Government will undertake an investigation to determine the cause of the defect and develop a scheme to repair the delaminating concrete.

The measures are needed to:

  • eliminate the risk of concrete falling on public and private land;
  • investigate the cause of the defect;
  • develop and implement a scheme to repair and prevent future defects of this nature.

Fencing and netting will remain in place until such time concrete repairs works is completed and the risk eliminated.

The start date for concrete repairs cannot be estimated at this time due to the complexity of the structures, however SWTRA on behalf of Welsh Government will endeavour to develop and implement the scheme as soon as possible.

Knights Brown Construction Ltd has been appointed as the Principal Contractor for the netting and fencing works.

AECOM has been appointed as the Designers and Supervisor of the fencing and netting works.

Fencing and netting work will start in 2022 whilst the design of concrete repairs has already begun.

Not on the M4. Lane closure and or temporary traffic lights may be needed to some parts of the local network.

Traffic will not be diverted – traffic lights will be used to allow roads to remain open.

During works: parking on local road may be restricted to enable the mobilisation of machinery to site. Details will be provided soon.

Works will require to be carried out overnight and during the daytime.

Digging and drilling are identified to be the noisiest activates. Measures are to be put in place to keep noise to a minimum and/or, as much as practical, undertake tasks at most appropriate times.

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